<%@page import="java.sql.*" %>
<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>数据库操作</title>
<style type="text/css">
h1{ color:red;}
</style>
</head>
<body>
<h1>数据库操作</h1>
<pre>
(1)创建数据库
(2)选择要操作的数据库
(3)创建表
(4)删除记录
(5)向表中插入记录
(6)修改记录
(7)查询记录
</pre><%!
public void showUsers(Statement st, JspWriter out){
	try(ResultSet rs=st.executeQuery("select * from users")){
		while(rs.next()){
			String name=rs.getString("xm");
			int age=rs.getInt("age");
			out.println("<p>"+name+","+age+"</p>");
		}
	
	}catch(Exception e){
}
	}

%>
<% 
Class.forName("com.mysql.cj.jdbc.Driver");
try(Connection cn=DriverManager.getConnection("jdbc:mysql://localhost:3306/","root","12qwas");
	   Statement st=cn.createStatement()){
	   st.executeUpdate("create database if not exists db666");
	   out.println("<p>成功创建数据库~</p>");
	   st.executeUpdate("use db666");
	   out.println("<p>成功创建数据库~</p>");
	   st.executeUpdate("create table if not exists users( xm varchar(4),age int)");
	   out.println("<p>成功创建数据库~</p>");
	   int count=st.executeUpdate("delete from users");
	   out.println("<p>成功删除"+count+"条记录</p>");
	   count=st.executeUpdate("insert into users(xm,age) values('张三',18),('李四',20)");
	   out.println("<p>成功删除"+count+"条记录,记录如下:</p>");
	   try(ResultSet rs=st.executeQuery("select * from users")){
		   while(rs.next()){
			   String name=rs.getString("xm");
			   int age=rs.getInt("age");
			   out.println("<p>"+name+age+"'/p");
		   }
	   }
	   count=st.executeUpdate("update users set xm='张三丰', age=81 where xm='张三'");
			   out.println("<p>成功删除"+count+"条记录,记录如下:</p>");
	   try(ResultSet rs=st.executeQuery("select * from users")){
		   while(rs.next()){
			   String name=rs.getString("xm");
			   int age=rs.getInt("age");
			   out.println("<p>"+name+age+"'/p");
		   }
	   }
}
%>
</body>
</html>